Colored stencil and method of making same



Dec. 5, 1933. H. P. ELLIOTT COLORED sTENcIL AND METHOD 0F MAKING SAMEFiled Oct. l2, 1952 lNVENTOR Harmon R Ellz'oi John Doe 5 Co.

H7 Leonard Sr. v

' New YorK C|fy- ATTORNEY UNITED `STATES PATENT OFFICE COLORED STENCILAND METHOD OF MAKING SAME Harmon P. Elliott, Watertown, Mass., assignorto Elliott Addressing Machine Company, a corporation of MassachusettsApplication October 12, 1932. Serial No. 637,396

10 Claims. (Cl. 1l-38.5)

The present invention relates to stencils made of coated Yoshino paper,orlike loose flbred fabric, and its main object is the rendering of thelegend or design cut or indented in the coating of y such stencil moreeasily read, both before and after the stencil has been inked.

`To this end the invention comprises a stencil blank or sheet having aiilm of coloring matter of the proper character to render it pervious toink after having been crushed by type blows and/or removable Wholly orin part by such blows on that side which I will call its back, and thestencil formed therefrom by indenting or cutting a legend or design inthe coating on the face of the loose iibred fabric which forms the baseof such stencil sheet.

In some aspects the present invention is an improvement on, ormodification of, that described and claimed in Patent No. 1,645,593granted October 18, 1927, to Erwin A. Geiger, in that a coloringmaterial of the character there described is preferably used.

Both inventions are primarily designed for use on stencil sheets orblanks made of Yoshino paper coated with a coagulated film of acomposition having a gelatine base, such as haybeen generally used inthe paper stencil art for 20 years. The coating of such stencil sheetsor blanks is generally done by drawing the sheet of Yoshino paper acrossthe surface of a bath of the coating liquid. As aresult the majorportion of the coating material is left on the under surface of thepaper, while only a minor portion soaks into the paper and through it tothe other surface. After the coating material has been allowed to set onthe Yoshino base it has a glassy surface and the Icoated sheet isslightly transparent, having an approximately white color. In cutting,or forming, the stencil from` such a sheet or blank it is placed in atypewriter with the more thickly coated surface presented to the actionof the type, or if the stencil is made by a stylus the marking by thestylus is done on the same surface, which, for brevitys sake, I willcall the front of the stencil sheet, the more thinly coated surfacebeing called the back.

Stencils made in the above described manner in the shape of small cardsare, and have been, for 20 years used extensively in addressingmachines, and in such use particulary it is important that the legendcut in the stencil in thisrnanner shall be legible to the user bothwhile being cut on the typewriting machine and afterwards during allperiods of use so that he can tell the name and address that will beprinted therefrom in the addressing machine, and make any necessarycorrections before the stencil goes into use. Such stencils asheretofore have been made out of the nearly white coated paper areslightly legible because the bottom surfaces of the indentations formedby the type 'are white, or at least more nearly white than are theremaining, unbroken or uncrushed surface portions of the sheet. This maybe due to the type blows breaking up the smooth glassy surface of thecoating and crushing the material under its face to a compacted iinewhite powder or granular mass, this effect being of the same characteras'that produced when a sheet of glass which is transparent is crushedand forms a white powder which is opaque. The result is also similar tothat produced by frosting a glass surface. Whatever the trueexplanation, the fact is that the portions of the surface of the stencilpaper which have been struck by the type appear more nearly white to theeye than the other portions of the sheet surface, which is usuallyslightly gray in tint. The difference between the white, opaque surfacesof the impressed characters and the nearly white glassy and slightlytransparent surface of the remainder of the sheet area is, however, onlyslightly noticeable and the desirability of a stencil card foraddressing machines which can be more easily read has long beenrecognized. In the effort to increase the legibility, the entire coatedsheet has been impregnated with dye or the coating material has beentinted before it was applied to the sheet, but then the color of theletters remains substantially the same as that of the other surfaceportions of the sheet. The Geiger patent above mentioned marked a stepin advance by proposing to use an alcohol dye, or one in a similarnon-acid vehicle which would not permeate the entire coating of thepaper, but would only mix with the surface portions thereof; and by alsoproposing to further limit the dyed zone by mixing such dye with shellacwhich would adhere to the surface, rather than permeate far into theinterior of the coating layer. But Geiger proposed to apply such dyesolution to the front of the stencil sheet and relied on the dispersiveeffect of the type blow on that surface to force the greater portion ofthe dyed layer of coating laterally away from under the type face, sothat the undyed fibre and residual, undyed coating material beneathwould appear, but this dispersion does not occur in practice to theexpected extent, and the Geiger invention has not yet gone intocommercial use, so far as I am advised.

I have discovered, however, that if a lm of coloring matter pervious toink after having been crushed by type blows, and/or removable Wholly orin part by such blows of the proper shade and of the general characterdescribed in said Geiger patent be applied to the back of the abovedescribed stencil blank, the legibility of the stencil producedtherefrom is greatly enhanced. I have obtained the best results with ared or orange dye. .Such a coating on the back of the stencil blankclearly shows through the slightly transparent coated sheet, when viewedfrom its front side, and after the type blow has crushed down theportion of this transparent coating beneath it and which has not beenpushed away laterally in the operation of cutting the stencil, and hastransformed it into a thin but opaque white mass through which thecoloring material behind it cannot be seen, the sharp contrast betweenthe white lettering so produced and the red or orange or otherrelatively dark color showing through the surrounding, unbroken, stillslightly transparent coating makes the legend stencilled readable withease.

If, also, the removable backing panel for a stencil card blank describedin my Patent No.

1,909,913, dated May 16, 1933, be used an additional advantage resultsfrom the fact that a portion of the dyed layer on the back of the cardis offset on the backing panel, so that after the latter has been tornfrom the stencil card it can be used as a proofing strip. A similaroffsetting would have occured on any backing sheet used when forming astencil sheet on a typewriting machine.

Also stencils made according to the present invention are more legibleafter being inked than are stencils not so made.

One form of stencil card made in accordance with the present inventionis illustrated in the accompanying sheet of drawing in which Fig. 1 is aperspective view of the stencil blank looking at the back thereof.

Fig. 2 is a cross section on line 2-2 of Fig. 1.

Fig. 3 is an enlarged detail cross section of the stencil sheet withcertain of the dimensions exaggerated for clearness. o

Fig. 4 is a front view of the stencil, to the back of which a iilm ofred dye has been applied, and the right hand portion of the face ofwhich has been inked, and

Fig. 5 is a face view of the backing panel removed.

Throughout the drawing like reference char` acters indicate like parts.1 indicates the frame of the stencil card generally which in the formshown is composed of a back frame section 6a and a front frame section 6between which the intermediate sheet of paper 5 has been cemented orpasted. '7 represents a stencil sheet preferably of coated Yoshinopaper, the edges of which have been pasted to the sheet 5. A panel 9 hasbeen partly cut out from sheet 5, being outlined by lines ofperforations or slits indicated at 2, 2, and having one end free to forma tab 3 by which it may be readily torn off, the above describedconstruction being that shown and described in my said Patent No.1,909,913 above mentioned. This latter feature, however, may usually beomitted, as such backing panel, being hygroscopic while the coated sheetis non-hygroscopic, the former is liable to absorb moisture, swell andbuckle so as to form blisters.

The stencil sheet 7, as shown in exaggerated form in Fig. 3, is composedof the sheet of Yoshino or other loose bred fabric 4, which has beencoated with a coagulated, slightly transparent iilm l0 by drawing thepaper across the surface of a bath of such material in liquid form, withthe result that a major portion of the coating is deposited on the underside of the paper sheet 4, a minor portion soaking into the paper andthrough to the other side to form a thin film on said other side. 8represents the lm of coloring material applied to the back of the coatedsheet by drawing the sheet across the surface of a bath of the coloringmaterial with the back of the sheet in contact with the surface of thebath or by any other proper method such as painting or rolling it on. 11represents an indentation produced by the blow of a type which haspushed the greater portion of the coating 10 on the face of the sheet toone side or the other and crushed the remainder beneath it to form adepressed surface 12 which may expose a portion of the fibres of theYoshino paper 4 beneath it, and has been rendered more perfectly white,but opaque, by such crushing, as above explained.

If a dark red or orange color dye is used, the color will show clearlythrough the slightly transparent coated sheet '7, while the bottoms ofthe type indentations 11 will be formed of opaque coating material whichhas been crushed and thereby given a nearly pure white surface whichcontrasts sharply with the red or orange or other relatively dark colorshowing through the uncrushed portions of the coated sheet. Any exposedYoshino fibres are also usually white.

In Fig. 4 at the right hand I have indicated at 13 an area of the frontof the stencil card which has been inked. The lm of ink usually of ablue black tint is so thin on the smooth surface of the coated paperthat it does not entirely blank out the red or other contrasting colorbeneath on the back of the stencil, but the effect on the eye is that ofa sheet having a color between blue and red or other contrasting color,if dark blue ink has been used. On the other hand, a larger quantity ofthe ink is absorbed per unit of area by the type indentations, so thatthe legend typed upon the stencil blank appears in a color substantiallythat of the ink used, which is contrasted quite clearly with thecomposite tint of the rest of the front of the stencil produced by thecombination of the red or other backing of contrasting colorand the darkblue ink lm on the front.

Probably more ink is deposited in the type indentations than on thesmoother surfaces of the coated sheet because of their depressed level,(which produces an intaglio effect) 'and also because of the greaterabsorptive power of the broken surface portions which have been bruisedby type blows. i

Other forms of coloring matter pervious to ink after having been crushedby type blows, and/or removable wholly or in part by such blows might besubstituted for that above described, if such substitutes would notpermeate the entire coating of the Yoshino, or, at least, not penetrateso deeply into it as to color the bottom surfaces of thetypeindentations on the other face of the sheet.

Preferably, to produce the best results, the absorptive capacity of thecoating layer, and the penetrating power of the applied dye or paintsolution, should be so related that the color will not extend to thefront surface of the Yoshino paper.

While I have here shown the area of the colored lm as co-extensive withthe window opening in the broader frame section 6a, it might be greateror less than that, and if the coloring solution were applied to theentire surface of a large sheet of coated paper before it was cut up toform a plurality of smaller stencil blanks such as'here shown, the areaof the coloring lm on each stencil card would then be coextensive withthat of the strip 4, of coated paper. Also such larger sheets if made inaccordance with my invention could be used in printing apparatusdesigned to cooperate with them for duplicating purposes. In such case aconsiderable portion of the advantageous results hereinabove describedwould also be realized.

I prefer te use for the purposes here described coloring matter of amineral nature, such as coal tar derivatives which are held in solutionor suspension by an alcohol vehicle and mixed with shellac, so that thecoloring lm created by such mixture has somewhat the nature of a coloredvarnish applied to the bacl; of the coated Yoshino sheet, with aconsiderable portion of Athe coloring matter remaining on that surfacethereof instead of penetrating any considerable distance into theinterior of the coating proper. As a result each type blow received incutting the stencil causes a portion of this coloring material, orcolored varnish, to crack olf and adhere to the backing sheet 9, thusoffsetting the stencil legend thereon, as indicated in Fig. 5. diminishthe legibility of the stencil but does produce a legible proof slipwhich may be led or put to other use. I am aware that it has beenheretofore proposed to use a separate colored backing sheet when sheetstencils are being cut on a typewriting machine, but such separatecolored sheet is, and has to be, removed before the stencil is used, forthe Very obvious reason that such separate sheet is impervious to ink.Consequently, after the stencil has been cut on the typewriting machineand removed from association with the colored backing sheet, itslegibility is destroyed, and this condition persists before and while itis being used in stencilling, or is in the files or is being inspectedto determine whether it should be used. Therefore the main advantages ofmy present invention are totally lacking when such prior art procedureabove referred to is employed. All these advantages on the other handpersist with the use of my present invention during the entire life ofthe stencil, which may endure for years and include 100,000 repetitionsof use of it in printing operations.

Having described my invention, I claim:

1. As a new article of manufacture, a` composite sheet for makingstencils comprising a base of loose fibredafabric, a coating for saidfabric adapted to be partially displaced and the remaining portionscrushed to an opaque condition by type pressure, the majorportion ofwhich coating is on that surface of said fabric to which the typepressure is to be applied, and a film of coloring matter pervious to inkafter having been crushed by type blowsand/or removablev wholly or inpart by such blows extending over the other and more thinly coatedsurface of said fabric. t

2. As a new article of manufacture, a composite sheet for makingstencils comprising a base of loose bred fabric, a coating for saidfabric adapted to be partially displaced and the remaining portionscrushed to an opaque condition by type pressure, the major portion ofThis does not Y which coatingV is on that surface of Asaid fabric towhich the type pressure is to be applied, and a film of coloring matterpervious to ink after having been crushed by type blows, and/orremovable wholly or in part by such blows extending over the other andmore thinly coated surface of said fabric, said composite sheet beingslightly transparent so that the portions of the front thereof notcrushed by type blows also appears to be colored by reason of the colorshowing through the body thereof.

3. An article of manufacture such as is defined in claim 2 in which saidcoloring matter is suspended in an alcohol vehicle mixed with shellac.

el. An article such as defined in claim 2 in which said coloring matterhas not penetrated said coating as far as the other surface of said basefabric.

5. An article such as defined in claim l in which said coating materialhas the quality of being rendered opaque by the crushing action of typeimpressed on its surface.

6. A paper stencil comprising a sheet of Yoshino paper saturated andcoated with a solution forming a slightly transparent body when set, anda film of dark coloring matter pervious to ink after v having beencrushed by type blows, and/or removable wholly or in part by such blowsformed on one surface of said sheet, while the other surface thereof haslimited opaque areas contrasting with said colored film and outliningthe matter to be stencilled; whereby said outlined matter is renderedclearly legible by said contrast with said colored film as a background.

7. A stencil such as dened in claim 6 in which the major portion of saidcoating is located on the surface bearing said limited opaque areas andthe latter are indented therein.

8. A stencil such as dened in claim 6 in which said opaque areas aresubstantially white in color.

9. The herein described method of rendering more legible a stencilcomposed of a sheet of Yoshino paper having a slightly transparentcoating capable of being indented or crushed by type y blows, whichcomprises applying to one surface of said coated sheet a film ofcoloring matter pervious to ink after having been crushed by type blows,and/ or removable wholly or in part by such blows which will notpenetrate far below said surface, and indenting the legend to bestencilled by type blows on the other surface.

l0. The herein described method of producing a legible stencil whichcomprises applying to one side of a sheet of loose bred paper asemitransparent coating which is capable of being broken down andrendered opaque and partly displaced by the blows of the type of atypewriting machine; applying to the other side of said coated sheet afilm of colored material pervious to ink after having been crushed bytype blows, and/or removable wholly or in part by such blows which willpenetrate only part way through it; and indenting the legend to bestencilled by type blows against the first mentioned surface; wherebythe colored lm shows through all portions of said typed sheet except theopaque areas lproduced by the type blows, the latter appearing in sharpcontrast with such colored background, and permitting ink to passtherethrough when the stencil f is used for printing said legend uponthe surface of an article placed beneath it. i

HARMON P. ELLIOTT.

